Give first the step you will use to separate the variable and then solve the equation:
(a) x – 1 = 0
(b) x + 1 = 0
(c) x – 1 = 5
(d) x + 6 = 2
(e) y – 4 = – 7
(f) y – 4 = 4
(g) y + 4 = 4
(h) y + 4 = – 4
(a) x - 1 = 0
Adding 1 to both sides of the equation we get,
x - 1 + 1 = 0 + 1
x = 1
(b) x + 1 = 0
Subtracting 1 from both sides of the equation we get,
x + 1 - 1 = 0 - 1
x = -1
(c) x - 1 = 5
Adding 1 to both sides of the equation we get,
x - 1 + 1 = 5 + 1
x = 6
(d) x + 6 = 2
Subtracting 6 from both sides of the equation we get,
x + 6 - 6 = 2 - 6
x = - 4
(e) y - 4 = - 7
Adding 4 to both sides of the equation we get,
y - 4 + 4 = -7 + 4
y = -3
(f) y - 4 = 4
Adding 4 to both sides of the equation we get,
y - 4 + 4 = 4 + 4
y = 8
(g) y + 4 = 4
Subtracting 4 from both sides of the equation we get,|
y + 4 - 4 = 4 - 4
y = 0
(h) y + 4 = - 4
Subtracting 4 from both sides of the equation we get,
y + 4 - 4 = - 4 - 4
y = - 8
Solve the following equations by trial and error method: (i) 5p + 2 = 17 (ii) 3m – 14 = 4
Write equations for the following statements:
(i) The sum of numbers x and 4 is 9.
(ii) 2 subtracted from y is 8.
(iii) Ten times a is 70.
(iv) The number b divided by 5 gives 6.
(v) Three-fourth of t is 15.
(vi) Seven times m plus 7 gets you 77.
(vii) One-fourth of a number x minus 4 gives 4.
(viii) If you take away 6 from 6 times y, you get 60.
(ix) If you add 3 to one-third of z, you get 30
Match the items given in Column I with one or more items of Column II.
Column I | Column II |
(a) A plane mirror | (i) Used as a magnifying glass. |
(b) A convex mirror | (ii) Can form image of objects spread over a large area. |
(c) A convex lens | (iii) Used by dentists to see enlarged image of teeth. |
(d) A concave mirror | (iv) The image is always inverted and magnified. |
(e) A concave lens | (v) The image is erect and of the same size as the object. |
- | (vi) The image is erect and smaller in size than the object. |